Conduit drainage

[Zee]

If conduit from roof runs down exterior, bends 90 and 90 again (total horizontal run about 3') and into a box......do I need drainage in the conduit (T or LB) itself at the low point ............ or do weepholes in the box suffice?

BTW - this is the latest fave correction of inspectors. For good reason too.

 

[Strathead]

If conduit from roof runs down exterior, bends 90 and 90 again (total horizontal run about 3') and into a box......do I need drainage in the conduit (T or LB) itself at the low point ............ or do weepholes in the box suffice?

BTW - this is the latest fave correction of inspectors. For good reason too.

IMO, the actual low point needs drainage. if that low point is in a box then weepholes in the box, if it is on the conduit the weepholes in the conduit.

 

[infinity]

Depends on the type of raceway. EMT will self drain through the terrible wet location fittings. RMC will drain through the couplings. For PVC drill a hole at the lowest point of the run if that isn't in a box.

 

[ptonsparky]

Weep holes in boxes or conduit bodies. I used to cut the gaskets at the low points. I’ve yet to figure out why a bell box designed for wet locations will allow water in via gaskets but not out.

 

[infinity]

Weep holes in boxes or conduit bodies. I used to cut the gaskets at the low points. I’ve yet to figure out why a bell box designed for wet locations will allow water in via gaskets but not out.

I do the same thing cut a notch in the bottom of the gasket around the bottom screw. It's amazing to see the boxes without the notch filled with water.

 

[jaggedben]

If conduit from roof runs down exterior, bends 90 and 90 again (total horizontal run about 3') and into a box......do I need drainage in the conduit (T or LB) itself at the low point

Well, yes, you do. Don't ask me about my experience with this.

............ or do weepholes in the box suffice?

Not if the conduit would fill with water below the box, no.

EMT will self drain through the terrible wet location fittings. RMC will drain through the couplings. ...

Not if the two 90s are bent with no coupling.

 

[infinity]

Not if the two 90s are bent with no coupling.

Of course. That would apply to any raceway that didn't have a fitting between the elbows.

 

[garbo]

Are the wires on the roof sealed so no air could travel indoors causing condensation. At a large slaughterhouse that I worked in we would drill drainage holes at an angle towards a wall ( if panel or box was mounted on the wall ). Would tape a piece of scotch bright pad over holes in case cleaning crew hit it with pressure washer.

 

[Master Nater]

as with any raceway or enclosure, if it's capable of holding water, it needs a way to let water out. whether you want it to or not, water will get inside. even if only from condensate from the air. so you'd better leave a way, to let it out. or water will make it's own way out by rusting through the bottom.

the same goes for weatherproof bell boxes. if you install one and fail to drill a weep-hole somewhere in the bottom lip, you just ruined that enclosure.

 

[Zee]

Left upper conduit is the one in question:

 

[Zee]

Weep holes in boxes or conduit bodies. I used to cut the gaskets at the low points. I’ve yet to figure out why a bell box designed for wet locations will allow water in via gaskets but not out.

may be collecting condensation from conduit run? and not water intrusion through gaskets on box....We have had water POUR out of a Solaredge inverter simply from years of condensation running down inside conduit and into the inverter. Water rose so high it fried the inverter.

 

[Zee]

Are the wires on the roof sealed so no air could travel indoors causing condensation. At a large slaughterhouse that I worked in we would drill drainage holes at an angle towards a wall ( if panel or box was mounted on the wall ). Would tape a piece of scotch bright pad over holes in case cleaning crew hit it with pressure washer.

Our rooftop conduit typically originates in a bell box with gasketed cover on roof. (We drill weepholes into that Bell box. ) So not sealed, no.

 

[Zee]

Left upper conduit is the one in question. See pic above.
I do not see the point (beyond a literal interpretation possibly of Code) to provide drainage at the "low point" , the 90 bend, in the upper, smaller conduit. I do not see the point, since it enters the lower SIDE of the box, and the box has drainage.
Water should cascade outta that conduit and into the bottom of the box, and drain.

Agree or fight me?

 

[Master Nater]

Left upper conduit is the one in question:

View attachment 2582552

if that's a nema 4/12 enclosure, i'd make sure to drill a couple of weep-holes into the bottom. the code allows for up to 1/4" drilled into enclosures. but i don't like going that large, as some bugs can crawl into 1/4" holes. i usually just use a self-tapping screw, that drills a 1/8" - 3/16" weep-hole. same goes for that LB conduit body on the very left. a small weep-hole in the bottom lip, that misses the screw-threads in the body. otherwise, that entire conduit will fill up.

 

[don_resqcapt19]

I do the same thing cut a notch in the bottom of the gasket

We do that with the conduit body gasket if we have a conduit body at the low point.

 

[jaggedben]

Left upper conduit is the one in question:

View attachment 2582552

I my opinion that's fine. Water will drain into the combiner which is NEMA3R. I originally thought you were describing a U shape.